FIG. 1 is a top sectional view of a conventional projection apparatus 1, which includes an outer casing 11, a light source 12 mounted within the outer casing 11, an optical engine 13 and a power source 14. The light source 12 is capable of generating light beams to the optical engine 13. The light source 12 preferably includes two lamps for generating sufficient light beams in order to enhance the lighting. The optical engine 13 is connected to the light source 12 so as to receive the light beams emitted from the light source 12. The power source 14 is used for supplying electrical power to the conventional projection apparatus 1.
The light source 12 usually generates intensive heat during operation of the conventional projection apparatus 1. Traditionally, an exhaust fan unit 15 is disposed adjacent to the light source 12 in order to dissipate the heat from an interior of the outer casing to an exterior thereof. The output shaft, the motor or the blades of the fan unit 15 tend to ruin or damage when the fan unit 15 is disposed too close to the light source 12. The intensive heat aggravates in case of that damage is occurred in the fan unit 15, and eventually results in damage to the conventional projection apparatus 1. Since the conventional projection apparatus 1 has double lamps with high watts and the situation for dissipating intensive heat aggravates when the fan unit 15 fails to dissipate the heat from within the outer casing 11.